Wellhead apparatus



WELLHEAD APPARATUS 4 Sheets-Sheet 1 Filed March 6, 1967 Dec. 3, 1968 c. c, BROWN ET Al.

WELLHEAD APPARATUS W m .i w aaN 5 mm mam 1, Q a 0 k e d H g m h m 67 m Filed March 6, 1967 Dec. 3, 1968 Filed March 6, 1967 c. c. BROWN ET AL 3,414,056

WELLHEAD APPARATUS 4 Sheets-Sheet 3 Dec. 3, 1968 c. c. BROWN ET AL 3,414,0'56

WELLHEAD APPARATUS 4 Sheets-Sheet 4 Filed March 6, 1967 BROWN $95K L. .4 F 5% \tf ,c/eERO 4.

JAMES IN yaw/M United States Patent 3,414,056 WELLHEAD APPARATUS Cicero C. Brown and James D. Mott, Houston, Tex.; said Mott assignor to Brown Oil Tools, Inc., Houston, Tex., a corporation of Texas Filed Mar. 6, 1967, Ser. No. 620,968 13 Claims. (Cl. 166-89) ABSTRACT OF THE DISCLOSURE A combination tree and hanger structure for a dual production well which provides diverging production flow passages and workover passages aligned with the production strings, removable plugs for sealing the workover passages and simplified guiding for orientation of the components of the wellhead apparatus.

Background of the invention This invention relates to improved wellhead apparatus for dual completion wells.

In the completion of wells, particularly wells in which the wellhead is located below the surface of the water, it is desirable to be able to perform operations within the well without having to remove the production flow lines. In dual completion Wells, it is desirable to be able to lower and support the two tubing strings on a tubing hanger without having to orient the tubing hanger with respect to the rest of the previously installed wellhead equipment and still be able to make tubing connections into said tubing hanger easily and quickly.

Wellhead structures which provide a smooth, full bore diverging production passage for each production tubing string and also a passage which is normally closed in direct alignment with the production tubing string have been used. In known structures of this type, the production passages extended from the tubing strings at an angle and plug members were provided to define a smooth full bore passage in the wellhead equipment to the angular production passage. Such plug members have been the source of continuing difiiculties in such installations because of the difliculty of providing proper orientation and because they are diflicult to maintain in alignment in their respective passages.

The present invention provides an improved wellhead structure for a dual string completion in which the tub ing hanger is set in the wellhead without orientation but provides orientation for the remainder of the equipment mounted thereabove. Also the improved apparatus provides smooth, full bore production passages which diverge from the tubing strings and improved plugs closing the openings aligned with the tubing string which are readily installed, are self-orienting, are not subject to misalignment and are readily removed to allow Work on the tubing strings without having to remove all of the tree structure above the tubing hanger or the production lines.

It is an object of the present invention to provide an improved wellhead apparatus for a dual string well which is suitable for use in marine well completions.

Another object of the present invention is to provide an improved dual production wellhead apparatus with a tubing hanger which orients the remainder of such apparatus.

A further object is to provide as an improved subcombination for a well completion apparatus, a plug adapted to seal the aligned passages in the tree structure and to define the smooth full bore diverging production passages which plug is not subject to misalignment and is properly oriented when landed.

Still a further object of the present invention is to provide an improved tubing hanger sub-combination for a dual production wellhead apparatus which is easily and quickly set in the wellhead and which provides guide means for orienting the tree structure connecting thereto.

Brief description of the drawings These and other objects and advantages of the present invention are hereinafter set forth with reference to the preferred embodiment illustrated in the drawings wherein:

FIGURE 1 is a longitudinal sectional view of the preferred form of wellhead apparatus of the present invention.

FIGURE 2 is a partial longitudinal sectional view of the improved plug shown in the wellhead apparatus in FIGURE 1.

FIGURE 3 is a transverse cross-sectional view of the wellhead apparatus taken along line 3-3 in FIGURE 1 to show the relationship of the plug and the diverging production line.

FIGURE 4 is a transverse sectional view taken along line 4-4 in FIGURE 1 to illustrate the tubing hanger and tree structures and the guiding means which functions to orient said tree structure with respect to said tubing hanger.

FIGURE 5 is another transverse sectional view and is taken along line 5-5 in FIGURE 1 to show the details of the tubing hanger.

FIGURE 6 is a sectional view of the tubing hanger taken along line 6-6 in FIGURE 5 showing the return flow connecting passages.

FIGURE 7 is a schematic sectional view of the lowering of the tubing hanger.

FIGURE 8 is a schematic sectional view showing the tubing hanger landed and the tubing strings cemented.

FIGURE 9 is a schematic sectional view illustrating the wellhead tree structure in place and production tubing connections made for production of well fluids.

FIGURE 10 is a partial schematic view showing the removal of the plug from one of the passages for the reworking of one of the production strings.

Description of the preferred embodiment When a well has been drilled and is ready for running of tubing strings, the tubular mandrel M, as shown in FIGURE 1, is positioned projecting from the upper end of the well bore. The tubular mandrel M includes an internal shoulder 10 on which the casing hanger 12 is seated with the casing C depending therefrom as best seen in FIGURES 7, 8 and 9. The tubular mandrel M also defines the seat 14 which is spaced above the casing hanger 12 and is adapted to receive the tubing hanger H. The upper end of tubular mandrel M defines the internal tapered seat 16, the internal threads 18 and the external groove 20. The tree body B is positioned partially on said tubing hanger H and partly in engagement with seat 16 and is held by remote controlled securing means S as hereinafter described. The tree body B is oriented with respect to the tubing hanger H by the orienting means 0.

The tubing hanger .H is designed to support tubing string 22 directly and tubing string 24 indirectly so that tubing string 22 may be lowered into the well bore attached to tubing hanger H and thereafter tubing string 24 is lowered through tubing hanger H with the collar 26 connected thereto and seating within the tubing hanger H or both strings may be lowered supported from tubing hanger H. The collar 26 and the tubing hanger H each define a recess adapted to receive stingers to communicate with the tubing strings, as hereinafter explained. As best seen in FIGURES 5 and 6, the tubing hanger H also defines the return flow passages 2-8 and 30 which provide communication through the tubing hanger H, exteriorly of the tubing strings. The sleeve 32 is secured to the tubing hanger H as an integral part thereof and has its upper end shaped to provide part of the aforementioned orienting means 0. Sleeve 32 is annular and extends upwardly above the tubing hanger H. The upper edge of sleeve 32 defines the upwardly opening slots 34 which are opposite each other and also the upwardly tapered surfaces 36 extending from the upper edge of each slot to provide the points 38 which also are opposite each other. Thus, any projection engaging the upper surface of sleeve 32 is guided down one of the surfaces 36 to one of the slots 34 as hereinafter more fully explained.

The tree body B has a lower outer diameter sutficiently small to enter the sleeve 32 and is oriented with respect thereto by the orienting means which includes the projections 40 extending outwardly from opposite sides of tree body B. Projections 40 are adapted to initially engage the surfaces 36 and travel down thereon causing tree body B to be rotated. When projections 40 are positioned in slots 34, the tree body B is properly oriented with respect to tubing hanger H.

Projecting downward from the lower end of tree body B are two stingers 42 and 44 which are adapted to enter and seat within the recesses defined by tubing hanger H and collar 26. These stingers 42 and 44 provide communication passageways from the tubing strings 22 and 24 to the two diverging passages 46 and 48 and the two parallel aligned passages 50 and 52 defined in tree body B. The upper end of each of the stingers 42 and 44 is tapered to provide the seats 54 and 56 on which the plugs 58 and 60, which are positioned in the aligned passages 50 and 52, seat.

The means S securing tree body B to the tabular mandrel M includes the flange 62 which is Welded or otherwise suitably secured to tree body B, the sleeve 64 containing a plurality of movable locking elements 66 and the pressure responsive collar 68. As shown, the sleeve 64 is secured to the flange 62 by the bolts 70 to depend downwardly from the outer edge of flange 62 in surrounding relation to the upper end of tubular mandrel M. The locking elements 66 are urged outwardly in sleeve 64 by springs 72. The collar 68 surrounds sleeve 62 and is slidable thereon responsive to fluid pressure in the upper and lower annular pressure chambers 74 and 76 which are defined by collar 68 and sleeve 62. Fluid pressure is intrdouced into chambers 74 and 76 by the lines 78 which connect from collar 68 to a suitable source of fluid under pressure. The interior of collar 68 defines the sloping cam surface 80 which is adapted to engage the outer surfaces of the locking elements 66 to move them inwardly into locking engagement with the groove defined in the exterior of tubular mandrel M. Thus, securing of tree body B to tubular mandrel M is accomplished remotely by actuation of collar 68 downwardly responsive to fluid pressure in chamber 76. In this position, the sealing element 82 carried 'by the tapered portion of flange 62 is seated on the seat 16. To release the securing means S, fluid pressure is exhausted from chamber 76 and delivered to chamber 74 causing collar 68 to move upwardly to release locking elements 66.

The upper end of tree body B is secured to and extended by ring 84 which is adapted to receive the cap 86. The cap 86 is suitably secured to ring 84 and includes the fishing neck 88 and the check valve 90. The check valve 90 is adapted to prevent any flow of fluids inwardly through cap 86 and to allow flow of fluids outwardly when the pressure under cap 86 exceeds the external pressure. The pin 92 is secured to ring 84 and is positioned with respect to aligned passages 50 and 52 to provide a guiding means to allow a stinger to seat in one of the stinger receiving recesses defined by the tree body B at the upper end of aligned passages 50 and 52.

The plug 60 which is shown in detail in FIGURE 2,

includes the body 94, the fishing neck 96, the latching means 98 and the sealing means 100. The body 94 defines the transition passage 102 through said body 94 which passage smoothly curves in one direction to provide a communication through the plug 60 from the interior of stinger 44 to the diverging passage 48. The lower end of body 94 defines and completely surrounds transition passage 102 and is tapered with respect to its longitudinal axis to engage the seat 56. When plug 60 has been lowered through the passage 52 into engagement with seat 56, the matching tapers on seat 56 and body 94 orient plug 60 to place the side outlet of passage 102 in registry with diverging passage 48. The plug 58 is identical with the plug 60 and is properly oriented in passage 50 by engagement with seat 54.

As can be readily seen from FIGURE 2, the latching means 98 is activated by exerting a downward force on fishing neck 96. When latched, the by-pass ports 104 are closed by the internal sleeve 106.

It is of particular advantage in the design of the plugs 58 and 60 that a portion of the plug body completely surrounds the lower end of the transition passage which is defined by the plug. By this construction, this lower ring portion of the plug body engages in the passage 50 or 52 to maintain the plug in alignment therewith and thereby eliminates cocking difliculties previously experienced with plugs. Another advantage achieved by this structure is the assurance that when the plug is seated and latched in its aligned passage, that the passage defined by the plug body is in registry with the diverging passage to provide a full bore, smooth contour flow passages from the tubing strings 22 and 24 to the production lines 108 and 110 which connect to the tree body B to conduct production fluids from the well to suitable production equipment (not shown).

In operation, when the drilling has been completed on a dual completion well, which as illustrated is a marine well, the casing C is supported on the casing hanger 12 which is seated on the shoulder 10 in the tubular mandrel M. The riser R is connected to the upper end of the tubular mandrel M by suitable remote controlled securing means similar to the securing means S previously described. Thereafter the tubing strings 22 and 24, supported from tubing hanger H are lowered through the riser R supported by the pipes P1, and P-2 as shown in FIGURE 7. It should be noted that tubing string 24 may be lowered into position in the well bore and thereafter tubing string 22 may be lowered through the tubing hanger H with collar 26 seating therein when tubing string is in place.

With tubing hanger H seated on the seat 14 defined by tubular mandrel M, the tubing may be cemented into the casing as shown in FIGURE 8. During cementing, the cement is pumped downwardly through pipes P-1 and P-2 and through tubing strings 22 and 24. The fluids in the well bore and the cement flow upwardly around the tubing strings, with well fluids flowing through return flow passages 28 and 30 in tubing hanger H. Balls 112 and 114 are positioned in passages 28 and 30, respectively, to prevent downward flow of fluids through passages 28 and 30.

When the cement has set, pipes P1 and P-2, riser R are removed and tree body B together with securing means S, the remote control lines 78 and the production lines 108 and 110 are all lowered into position. The lower end of tree body B enters the interior of tubular mandrel M and when the projections 40 engage the tapered surfaces 36 on sleeve 32, the tree body is rotated as it moves downwardly to position the projection 40 in the slots 34, thus orienting tree body B to tubing hanger H to assure that the stingers 42 and 44 projecting below tree body B enter into the recesses defined by tubing hanger H and collar 26. In this position, the securing means S is actuated to latch tree body B to tubular mandrel M. The tree body B is lowered into such position with the plugs 58 and 60 seated in the aligned passages 50 and 52. In this position, illustrated both in FIGURES l and 9, production of the well fluids may be commenced. The flow is through the tubing strings, the stingers, the passages defined by the plugs, the diverging passages and the production lines.

Whenever it is desirable to perform some operation requiring access to one of the tubing strings, the cap 86 is removed from the ring 84 and the tool T is lowered onto and latched to the ring 84 (FIGURE by a suitable remote controlled latch. The tool T includes a skirt 116 depending from the body 118 which is adapted to surround the exterior of ring 84 and the tubular stinger 120 extending downwardly from the body 118. The stinger 120 is olTset from the center of the body 118 and is adapted to seat in either one of the recesses defined in the upper end of the aligned passages. The stinger 120 also communicates through the body 118 to the workover pipe 122. Thus, as shown in FIGURE 10 when the tool T is lowered onto ring 84, the internal slot 124 defined by skirt 116 is provided to receive the projection 92 and thereby orient tool T so that stinger 120 is positioned in communication with a preselected one of the aligned passages. Skirt 116 is adjustable with respect to body 118 so that the desired aligned passage with which the stinger 120 is to connect, may be preselected. As shown in FIGURE 10 when tool T has been latched to ring 84 suitable equipment may be lowered through pipe 122 to remove the plug 60 and thereby allow direct access to the tubing string 24. Tubing string 22 becomes accessible merely by rotating skirt 116 one-half turn on body 118 before the tool T is lowered. Then the plug 58 may be removed and work performed in tubing string 22. Screw 126 is provided to engage through body 118 into the single recess defined in the upper end of skirt 116. This assures the proper preselection of the aligned passage which is to be engaged by stinger 120.

From the foregoing it can be seen that the present invention provides an improved wellhead completion structure for a dual production well with improved orienting means for orienting the completion equipment to the tubing hanger without having to orient the tubing hanger in the well bore. This improved completion equipment provides aligned and diverging passages communicating with each tubing string and improved plugs seated in the aligned passages and defining smooth contoured, full diameter passages communicating from the tubing strings to the diverging passages which plugs are assured to be oriented when latched in the aligned passages and are not subject to cocking or misalignment in the aligned passages so that they are readily removed to provide an aligned access to the tubing strings. The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made within the scope of the appended claims without departing from the spirit of the invention.

What is claimed is:

1. A wellhead apparatus adapted to be installed on a tubular mandrel having an internal seat, said apparatus comprising,

a tubing hanger positioned in said tubular mandrel on said seat,

said tubing hanger adapted to support at least two production tubing strings,

a tree body positioned within said tubular mandrel,

said tree body defined at least two passages adapted to be aligned with said tubing strings and a diverging passage extending from each of said aligned passages, means orienting said tree body with respect to said tubin hanger whereby said diverging and said aligned passages are in communication with said tubing 6 strings when said tree body is seated in said tubular mandrel,

means closing said aligned passages and means securing said tree body to said tubular mandrel.

2. A wellhead apparatus according to claim 1, wherein said means closing said aligned passages includes,

plugs seated in said tree body and closing said aligned passages,

each of said plugs defining a transition flow passage communicating between said aligned passages and said diverging passages whereby full bore smooth transition flow passages communicate from said tubing string to said diverging passages.

3. A wellhead apparatus according to claim 2, including means for orienting said plugs in said aligned passages whereby said transition passages register with said diverging passages.

4. A wellhead apparatus according to claim 3, wherein said orienting means for said plugs includes,

an upwardly facing shoulder defined by said tree body surrounding each of said aligned passages,

said shoulders being angularly positioned with. respect to the axis of said aligned passages,

the lower end of said plugs being tapered at an angle whereby when said lower end of each of said plugs is seated in engagement with its respective shoulder, said transition passages register with said diverging passages.

S. A wellhead apparatus according to claim 2, wherein the lower end of each of said plugs completely surrounds said transition passages defined thereby, and

said transition passages defined by said plugs extend upwardly and curve outwardly through the side of said plugs in a smooth curve.

6. A wellhead apparatus according to claim 1, wherein said orienting means includes,

an annular sloping path terminating in a vertical slot defined by said tubing hanger, and

means on said tree body adapted to engage said path and enter into said slot to orient said tree body on said tubing hanger.

7. A wellhead apparatus according to claim 1, wherein said orienting means includes,

a sleeve secured to said tubing hangar and extending upwardly therefrom,

the upper edge of said sleeve being con-toured to define at least one seated position,

means secured to said tree body and adapted to engage and ride on the upper edge of said sleeve while said tree body is being lowered into seatedposition whereby said tree body is oriented to provide registry between said aligned passages and said production tubing strings.

8. A wellhead apparatus according to claim 1, wherein said tubing hangar defines an upwardly facing socket in communication with each of said production tubing strings,

said tree body includes a tubular projection extending from each of said parallel passages,

each of said projections adapted to seat in one of said sockets to provide communication between said tubing strings and said aligned passages.

9. A wellhead apparatus according to claim 2, including means releasably latching said plugs in said aligned passages whereby said plugs may be removed therefrom individually to open communication through said aligned passages to said tubing strings independently of said divergent passages.

10. A wellhead apparatus adapted to be installed on a tubular mandrel having an internal seat comprising,

a tubing hanger positioned within the tubular mandrel on said seat and adapted to support at least two production strings,

a sleeve secured to said tubing hanger and extending upwardly therefrom,

said plug body defining a smooth transition passage communicating from said parallel passage below said plug body to the divergent passage,

the lower end of said plug body completely surrounding said transition passage whereby the circumference of the lower end of said plug engages said tree body to prevent cocking of said plug.

13. The sub-combination with a wellhead apparatus which includes a tree body defining at least two parallel passages and at least two divergent passages with the divergent passages communicating with the parallel passages, of a plug comprising,

PHSSEgCS, 10 each of said diverging passages extending from one of said aligned passages, each of said plugs defining a smooth full bore passage adapted to seal said passages,

a plug adapted to seat in one of said parallel passages,

and

each of said plugs defining a smooth gull bore passa e latching means connected to said plug body and adapted communicating between said aligned passage and said to releasably latch said plug body in said parallel diverging passage, passage in said tree body,

means orienting said plug in said passage, and said plug body definin a smooth transition passage means securing said tree body to said tubular mandrel. communicating from said parallel passage below said 11. A wellhead apparatus according to claim 10 plug body to the divergent passage,

the lower end of said plug body being tapered with respect to the longitudinal axis of said plug body and when seated in said tree body, said tapered orienting said transition passage into registry with said diverging passage.

wherein said plugs include,

means releasably latching said plugs in said aligned passages whereby said plugs may be removed to provide an in-line access to said tubing strings.

12. The sub-combination with a wellhead apparatus which includes a tree body defining at least two parallel passages and at least two divergent passages with the divergent passages communicating with the parallel passages of a plug comprising,

References Cited UNITED STATES PATENTS a plug body adapted to seat in one of said parallel pas- 3,101,118 3/1963 Culver et a1 sages, and 3,223,164 12/1965 Otternan 166-.6 latching means connected to said plug body and adapted 3,354,961 11/ 1967 Pennington 166-.5

to releasably latch said plug body said parallel passage in said tree body, JAMES A. LEPPINK, Primary Examiner. 

